There are many dentifrice additives which are incompatible with aqueous systems of typical dentifrice formulations. One way of overcoming this incompatibility problem is to formulate such additives in a non-aqueous (anhydrous) formulation. However in addition to circumventing the water incompatibility problem, such formulations must also be successful from a consumer acceptance standpoint and demonstrate, for example, acceptable taste, consistency and adequate foaming on brushing of teeth.
U.S. Pat. No. 3,574,824 (Warner-Lambert) describes an anhydrous toothpaste base comprising inter alia an oil, a combination of polyethylene glycols and a non-toxic, non-ionic emulsifier which is a mixture of glycerides. U.S. Pat. No. 3,574,824 discloses that an experimental paste was made using oily liquids, such as vegetable oil or extra light mineral oil, and a suitable surfactant. However when the paste was brought into contact with water during brushing there was insufficient foaming in the oral cavity. This was thought to be due to the fact that the foaming agent (sodium lauryl sulphate) was “hindered” in the anhydrous mass and was unable to concentrate at the air-water interface during brushing to form air bubbles or foam.
U.S. Pat. No. 4,647,451 (Colgate-Palmolive Company) describes anhydrous dentifrice compositions having desirable rheological, sensory and hygienic characteristics containing a polysaccharide gum and glycerine humectant. According to U.S. Pat. No. 4,647,451, such compositions comprise organic surface active agents which may be anionic, non-ionic, ampholytic, or cationic in nature. Compositions exemplified therein contain sodium lauryl sulphate as the sole surfactant.
U.S. Pat. No. 5,670,137 (L'Oreal) describes a dentifrice composition containing an anhydrous medium comprising glycerine, at least one hydroxyethylcellulose, at least one pyrogenetic silica. According to U.S. Pat. No. 5,670,137 such a composition also contains one or more foaming surfactants which may be anionic, amphoteric, zwitterionic, cationic or non-ionic. Compositions exemplified therein contain sodium lauryl sulphate as the sole surfactant.
WO96/03108 (SmithKline Beecham plc) and WO 2002/038119 (SmithKline Beecham plc) both describe non-aqueous dentifrice compositions. Anionic, cationic, non-ionic and amphoteric surfactants are disclosed for use as suitable surfactants. A particularly preferred anionic surfactant is identified as sodium methyl cocyl taurate, marketed under the name “Adinol CT 95”, this being the sole surfactant exemplified for use in the compositions therein.
WO2005/063185 (Novamin Technology Inc.) describes non-aqueous compositions of bioactive glass particulates in a non-aqueous carrier of the type disclosed in U.S. Pat. No. 5,882,630 (Gates). U.S. Pat. No. 5,882,630 corresponds to the US patent derived from WO96/03108, discussed above. According to WO2005/063185, compositions therein may optionally comprise agents conventionally used in dentifrice formulations including, for example, a foaming agent such as sodium lauryl sulphate. Compositions exemplified therein contain sodium lauryl sulphate as the sole surfactant.
WO2010/115037 (Colgate-Palmolive Company) describes non-aqueous compositions comprising carrageenan or a carboxymethylcellulose gum, a humectant and a bioacceptable and bioactive glass. According to WO2010/1155037, compositions therein may comprise additives conventionally used in dentifrice compositions including for example a surfactant such as sodium lauryl sulphate. Compositions exemplified therein contain sodium lauryl sulphate as the sole surfactant.
Whilst the non-aqueous compositions described in the prior art address some of the problems encountered with formulating dentifrice additives that are incompatible with aqueous-based systems, there nevertheless remains a need for alternatives. Ideally such alternative compositions should further demonstrate one or more properties that are key drivers of consumer acceptance including, for example, having consumer-acceptable organolpetic properties. Ideally the organolepic properties of such a composition will be at least as good as or preferably improved over those seen in comparable, marketed non-aqueous dentifrice products.
It is an object of the invention to provide such a composition.